Okay, writing the followup post ON the '87 model.
It cleaned up fairly well with some Oxi-Clean and agitation on the keycap bag. There were some spots of orangey-brown goo, and it had wicked inside some of the two-piece keys. I suspect this keyboard was decommissioned after a Coke accident. Given the vintage, possibly New Coke.
It feels a bit duller-- a touch quieter, a touch more pressure than the Customizer 104 next to it. It lost two more rivets during the cleaning process (total: 8 as far as I know)
Relevant photos:
* Proof I'm not blowing smoke about the date.
* Stabilizer bars for numpad + and enter.
* Partial reassembly. The Das M. This is the first one I've seen with all the key heads the same colour.
* LED panel. Note the individually-wired cable.
* Inner assembly label. Our new lesson: Someone who signed his initials "W" is responsible for those rivets that pop. We can track him down now!
Oddity: The |\ key sits a littele higher than others in its row. This is also true or the Customizer, but it's less prominent.
I had to steal spare keycaps for F8 and F11 from a later board. The F8 text is too low, and the F11 too delicate)
